A prospective study evaluating sleep quality in Failed Back Surgery Syndrome patients treated by multicolumn spinal cord stimulation: study design protocol and presentation of the study population.

BACKGROUND AND PURPOSE: One of the main consequences of chronic pain syndrome is major impairment of the quality of sleep. Chronic pain and insomnia are independently linked to significant reductions in quality of life and psychiatric morbidity. Recent studies have suggested the efficacy of spinal cord stimulation (SCS) for the treatment of the back pain component in failed back surgery syndrome (FBSS) patients using a multicolumn lead. The main aim of this pilot study is to assess the influence and potential benefits of SCS on sleep quality in refractory FBSS patients implanted with multicolumn SCS and enrolled in the French multicentre ESTIMET study. METHODS: This is a single-centre, comparative, exploratory, pilot study. Sixteen FBSS patients enrolled in the ESTIMET study and implanted with multicolumn SCS will be monitored for 6months after implantation. Sleep parameters will be recorded by polysomnography, Psychomotor Vigilance Test and Osler tests, actigraphy, sleepiness scales, and sleep quality testing. Sleep will be evaluated before (at the inclusion visit) and after SCS implantation (at the 6-month visit). Secondary objectives will also assess the impact of SCS lead programming (mono vs. multicolumn SCS) and the influence of position-adaptive stimulation at night on sleep quality. TRIAL STATUS: The first patient of this ancillary study was enrolled on 21 May, 2012 and recruitment has now been achieved. Primary endpoint findings are expected to be available in 2015. CONCLUSION: By providing an analysis of the quality of sleep in chronic pain patients who are candidates for implanted neurostimulation, this new approach focuses on an important aspect of quality of life often overlooked in these poly-medication patients. It could show a real clinical benefit and underestimation of these analgesic innovative expensive techniques, where medico-economic analysis, would or would not promote access.

Non-surgical management of posterior positional plagiocephaly: orthotics versus repositioning.

OBJECTIVE: Evaluate from the literature, the evidence of comparative efficiency of non-surgical treatments (orthotics or head repositioning therapy) in posterior positional plagiocephaly. MATERIAL AND METHODS: Systematic review from scientific articles (original cohort studies and review of literature), published in French or in English, searched on five online literature data bases, comparing non-chirurgical treatments (repositioning and orthotics therapy) for deformational plagiocephaly. A standardized method guidelines (Critical Review Form-Quantitative Studies) has been used. RESULTS: Only 11 cohort studies met the inclusion criteria and six reviews of literature were analyzed. Many biases have been identified, most of the time, favoring the repositioning groups (older infants and plagiocephaly more severe). CONCLUSIONS: Several different orthotics seem to correct head deformities better and faster than repositioning protocols. Evaluation methods, treatment indications and long-term efficacy should be clarified. Studies about treatment risks are warranted.

Psychological health in central hypersomnias: the French Harmony study.

BACKGROUND: A large observational French study of central hypersomnia, including narcolepsy with cataplexy (C+), without cataplexy (C-) and idiopathic hypersomnia (IH), was conducted to clarify the relationships between the severity of the condition, psychological health and treatment response. METHODS: 601 consecutive patients over 15 years of age suffering from central hypersomnia were recruited on excessive daytime sleepiness, polysomnography and Multiple Sleep Latency Test (MSLT) results. 517 (47.6% men, 52.4% women) were finally included: 82.0% C+, 13.2% C- and 4.8% IH. Face to face standardised clinical interviews plus questionnaires (Epworth Sleepiness Scale (ESS), short version Beck Depression Inventory (S-BDI), Pittsburgh Sleep Quality Index (PSQI) and 36-item Short Form Health Survey (SF-36)) were performed. Patients affected with a different diagnosis and with and without depressive symptoms were compared. RESULTS: Mean ESS and body mass index were higher in C+ compared with C-/IH patients. Half of the patients (44.9%) had no depressive symptoms while 26.3% had mild, 23.2% moderate and 5.6% severe depressive symptoms. C+ patients had higher S-BDI and PSQI and lower SF-36 scores than C-/IH patients. Depressed patients had higher ESS scores than non-depressed patients, with no difference in age, gender, duration of disease or MSLT parameters. Finally, C+ patients treated with anticataplectic drugs (38.7%) had higher S-BDI and lower SF-36 scores than C+ patients treated with stimulants alone. CONCLUSION: Our data confirmed the high frequency of depressive symptoms and the major impact of central hypersomnias on health related quality of life, especially in patients with cataplexy. We recommend a more thorough assessment of mood impairment in central hypersomnias, especially in narcolepsy-cataplexy.

[Obstructive sleep apnoea syndrome (OSAS) in women: a specific entity?]. / Pathologie pulmonaire au féminin: le SAOS de la femme, une entité particulière?

Despite a variable prevalence in the literature, OSAS is characterized by a higher frequency in men. This study involved a review of published data describing the impact of gender on features of OSAS. In women, OSAS seems to be associated with certain anatomical factors such as more significant obesity, a thinner oropharyngeal junction, a shorter uvula and reduced upper airway (UA) collapsibility, in comparison with men. Sleep related breathing disorders observed during pregnancy are more likely UA resistance syndrome than true OSAS, and are associated with severe fetal and maternal complications that could be improved by the use of nasal CPAP. Though OSAS symptoms are underestimated by women, the Epworth score as well as snoring are not influenced by gender. Gender does not seem to be a risk factor for increased mortality. Compliance with nasal CPAP is identical in both sexes, but oral appliance seem to be more effective in women. Further studies are needed to produce the required complementary data to confirm specific sex-related features in the diagnosis and treatment of OSAS.

Structural analysis and application to brain imaging.

Our goal is to organize the ElectroEncephaloGram (EEG) signal so as to describe and image various brain activities. Our work is based on a data structure, a graph, which sums up the brain activity in the spatial, temporal and frequency domains. From the information contained in the time-frequency map of EEG signals, a graph is constructed. In order to analyze the complexity of the signal, our method is based on a multi-scale approach with several levels of information extraction. To compare different EEG signals, we use techniques of graph-matching with our data structure. The developed algorithm is based on the A* algorithm that allows us to compare variations of the recorded EEG in term o f latency, frequency, energy and activated areas. The results of this project show first, that the graph is an appropriate tool to reduce the cortical activity complexity, and second, that graph-matching offers some interesting perspectives in order to describe functional brain activity.

[Cigarette smoking and sleep disturbance]. / Tabagisme et troubles du sommeil.

INTRODUCTION: Sleep disturbances may make smoking cessation more difficult and relapses more frequent. STATE OF THE ART: Nicotine increases vigilance and decreases sleeping time. Cigarette smoking is associated both with difficulty initiating and maintaining sleep. The disruption is associated with arousals on EEG recordings. Smoking promotes snoring and obstructive sleep apnoea. Insomnia is recognised as one of the criteria for nicotine withdrawal syndrome. Awakening from sleep and daytime sleepiness can occur frequently in this situation and are predictive factors for relapse. Nicotine replacement therapy itself induces frequent awakenings, a decrease in total sleep duration, early morning waking, dreams and sometimes nightmares with associated arousals on EEG. Sleep disruption is the most common side effect observed with bupropion when used as an aid in smoking cessation. PERSPECTIVES: Sleep disturbance must be taken into account in smoking cessation programs. More detailed investigations are needed, both clinical studies looking at measures of the main sleep parameters using sleep diaries and more detailed studies using polysomnography. CONCLUSION: In smokers, sleep disturbances must be taken into account, because they increase cardio-vascular and cerebro-vascular morbidity. During smoking cessation, relieving these disturbances should make quitting easier and prevent relapses.

[Evaluation of trypan blue toxicity in idiopathic epiretinal membrane surgery with macular function test using multifocal electroretinography: seven prospective case studies]. / Evaluation de la toxicité du bleu trypan dans la chirurgie des membranes épirétiniennes idiopathiques en testant la fonction maculaire par l'électrorétinogramme multifocal. Etude prospective sur 7 cas.

INTRODUCTION: Idiopathic epiretinal membranes are considered the consequence of glial proliferation through a defect of the internal limiting membrane and can induce a functional macular syndrome associating mainly metamorphopsia and visual acuteness. Visual disturbance is not bound to the area and the degree of transparency of the membrane, but to distortion of external layers of the retina. Multifocal electroretinography (ERGm) can assess the macular area and retina extending 20 degrees. We used this tool to study macular function pre- and post-operatively with seven patients presenting idiopathic epiretinal membrane. PATIENT AND METHOD: All patients had successful vitrectomy, with 0.2 ml of 0.15% trypan blue (TB) staining to facilitate peeling. This stain is not toxic for the pigment epithelium but it becomes so for photoreceptors at doses exceeding 0.2%. We tried to estimate the echo of TB 0.15% on photoreceptors through this exam. An ERGm was done 1 week before the operation as well as 1 month and 4 months after on 14 eyes of seven patients with ERMs. RESULTS: Results show a pre-operative decrease in the electrical retinal response densities in the foveal, perifoveal and parafoveal areas. One month after operation, no significant difference was found compared to pre-operative results. However, at 4 months, an improvement of the retinal response density was observed. Retinal response densities in the macular area increased progressively after ERM surgery. CONCLUSION: The 0.15% TB facilitated ERM peeling and does not seem to present any retinal toxicity.

Pharmacokinetic-pharmacodynamic modelling of the electroencephalogram effect of imipenem in rats with experimental hypovolaemia or endotoxaemia.

OBJECTIVES: The epileptogenic activity of imipenem in rats with experimentally induced hypovolaemia or endotoxaemia was investigated by pharmacokinetic-pharmacodynamic modelling of the electroencephalogram effect. METHODS: Hypovolaemia was induced by removal of 30% of the blood volume and endotoxaemia by intravenous lipopolysaccharide injection. RESULTS: Imipenem clearance and volume of distribution values of 16.4+/-1.1 mL/min per kg and 357+/-49 mL/kg (mean+/-S.E.M.) in healthy rats (n=5), were significantly reduced in hypovolaemic (n=6) and endotoxaemic (n=6) animals. A dose reduction from 250 mg/kg to 120 mg/kg was necessary in endotoxaemic rats. The pharmacokinetic-pharmacodynamic model with an effect compartment previously developed in healthy rats described the data adequately and pharmacodynamic parameters in hypovolaemic and endotoxaemic rats were not significantly different from corresponding values estimated in the control group. CONCLUSION: Hypovolaemia and endotoxaemia only had an effect on imipenem pharmacokinetics.

Do robots need to sleep?

The present paper exposes algorithmic results providing a vision about sleep functions which complements biological theory and experiments. Derived from the algorithmic theory of information, the theory of adaptation aims at quantifying how an inherited or acquired piece of knowledge helps individuals to survive. It gives a scale of complexity for survival problems and proves that some of them can only be solved by a dynamical management of memory associating continuous learning and forgetting methods. In this paper we explain how a virtual robot "Picota" has been designed to simulate the behavior of a living hen. In order to survive in its synthetical environment, our robot must recognize good seeds from bad ones, and should take rest during night periods. Within this frame, and facing the rapid evolution of to-be-recognized forms, the best way to equilibrate the energetic needs of the robot and ensure survival is to use the nightly rest to reorganize the pieces of data acquired during the daily learning, and to trash the less useful ones. Thanks to this time sharing, the same circuits can be used for both daily learning and nightly forgetting and thus costs are lower; however, this also forces the system to "paralyse" the virtual robot, and therefore the night algorithm is reminiscent of paradoxical (REM) sleep. The algorithm of the robot takes advantage of the alternation between wakefulness or activity and the rest period. This diagram quite accurately recalls the REM period. In the future, the convergence between the neurophysiology of sleep and the theory of complexity may give us a new line of research in order to elucidate sleep functions.

[Improvement in swallowing difficulties treated by subcutaneous apomorphine infusion after deep brain stimulation in Parkinson's disease]. / Amélioration des troubles de la déglutition par l'apomorphine en perfusion sous cutanée au décours de la mise en place d'électrodes de stimulation cérébrale profonde, dans la maladie de Parkinson.

In Parkinson's patients, swallowing difficulties may result in inhalation pneumonia, with a potentially serious prognosis. They may be revealed by withdrawal of L-dopa, especially after deep brain stimulation surgery. The following two cases illustrate the usefulness of apomorphine.

[Sleep apnea syndrome in the elderly]. / Le syndrome d'apnées du sommeil du sujet âgé.

INTRODUCTION: Sleep apnoea/hypopnoea syndrome (SAHS) is distinct in the elderly as age-related co-morbidity may be aggravated by sleep-related breathing disorders or may mask typical clinical symptoms. STATE OF ART: The SAHS prevalence in the elderly varies from one study to another, with an average rate of 25% that might increase according to the importance of associated pathologies. Clinical symptoms tend to be the neurological manifestations of excessive daytime sleepiness and cognitive deterioration. PERSPECTIVES: Treatment of SAHS should include weight reduction strategies if obesity is present. There is no role for surgery in this age group. On the other hand, adjustable oral appliances can be used depending on the severity of the SAHS, but nasal continuous positive airway pressure (CPAP) remains the most effective therapy available. Acceptance of and compliance with CPAP treatment is as good in this age group as in younger patients, with remarkable effectiveness in terms of improvement in daytime sleepiness and cognitive function. However, the effectiveness of treatment for SAHS is related to the level of symptoms present and this should be taken into account when making a therapeutic decision. CONCLUSIONS: These results fully justify treatment of SAHS in the elderly, but the decision to treat should be governed by the level of clinical symptoms from SAHS.

[Respiratory disorders during sleep in the pregnant woman]. / Troubles respiratoires au cours du sommeil de la femme enceinte.

Sleep disordered breathing can occur during pregnancy due to the development of hormonal changes and respiratory function abnormalities that perturb patency of the upper airways. Habitual snoring has been described in 25 p. 100 of the women during the third trimester of pregnancy. The incidence of sleep apnea hypopnea syndrome is unknown due to the lack of longitudinal epidemiological data, and results of the main studies are in favor of upper airway resistance syndrome. However, these sleep-related breathing disorders are more frequently associated with maternal and fetal complications such as maternal hypertension, pre eclampsia and intrauterine growth restriction. This article points out the importance of such associations because of the efficacy of continuous positive airway pressure on the regression of these nocturnal respiratory and vascular complications.

[Sleep apnea syndrome in the elderly]. / Le syndrome d'apnées du sommeil du sujet âgé.

INTRODUCTION: Sleep apnoea/hypopnoea syndrome (SAHS) is distinct in the elderly as age-related co-morbidity may be aggravated by sleep-related breathing disorders or may mask typical clinical symptoms. STATE OF ART: The SAHS prevalence in the elderly varies from one study to another, with an average rate of 25% that might increase according to the importance of associated pathologies. Clinical symptoms tend to be the neurological manifestations of excessive daytime sleepiness and cognitive deterioration. PERSPECTIVES: Treatment of SAHS should include weight reduction strategies if obesity is present. There is no role for surgery in this age group. On the other hand, adjustable oral appliances can be used depending on the severity of the SAHS, but nasal continuous positive airway pressure (CPAP) remains the most effective therapy available. Acceptance of and compliance with CPAP treatment is as good in this age group as in younger patients, with remarkable effectiveness in terms of improvement in daytime sleepiness and cognitive function. However, the effectiveness of treatment for SAHS is related to the level of symptoms present and this should be taken into account when making a therapeutic decision. CONCLUSIONS: These results fully justify treatment of SAHS in the elderly, but the decision to treat should be governed by the level of clinical symptoms from SAHS.

Relationship between sleep apnoea syndrome, snoring and headaches.

There is still a controversy regarding the relationship between sleep apnoea syndrome and headaches, especially morning headaches. Our objectives were: (i) to compare the prevalence and the clinical data of headaches in sleep apnoea syndrome (SAS) and control (snorers) groups defined by polysomnographic recording; (ii) to analyse the clinical improvement of headaches with appropriate treatment; and (iii) to correlate headaches with mood disorders, and nocturnal respiratory and architectural sleep parameters in order to understand the underlying pathophysiological mechanisms. This is a prospective study of 324 consecutive patients referred to our sleep centre for snoring. Of these, 312 patients who underwent sleep polysomnography were finally included. Patients and controls were interviewed about their medical past, headache history and clinical characteristics, their daytime sleepiness (Epworth's sleepiness scale) and their mood disorders (Zerssen's scale). Follow-up of patients with headaches (SAS and control groups), treated or not, was also assessed. According to our definition of SAS, patients were dissociated in SAS (n=164) and snorers (n=148). Fifty-three SAS patients had headaches, of whom 58.5% (n=30) suffered from morning headaches. However, there was no statistical difference between the two groups concerning the prevalence and the clinical characteristics of headaches. In addition, headaches and morning headaches were not correlated with nocturnal respiratory and architectural sleep parameters, nor with excessive daytime sleepiness, but were strongly correlated with mood disorders. In 36 SAS patients, headaches improved under treatment, but this was not statistically different from what was found among untreated snorers. Headaches and morning headaches are common in patients with SAS but may be considered as a non-specific symptom. The underlying mechanisms are not fully elucidated but depression could play an important role. Despite this absence of specificity, the treatment of SAS, especially nasal continuous positive airway pressure, leads to an improvement in headaches in several cases.

[The sleep apnea syndrome: diagnosis and management in general practice. A descriptive survey of 579 French general practitioners]. / Le syndrome d'apnées hypopnées du sommeil (SAHS): diagnostic et prise en charge en médecine générale.

General practitioners (GP's) should be the first to recognise the sleep apnoea/hypopnoea syndrome (SAHS) and could play a major role in the follow up of patients treated with continuous positive airways pressure (CPAP) at home. We have carried out a prospective study in order to evaluate the knowledge and diagnostic and therapeutic practice of GP's in relation to SAHS. 579 GP's agreed to participate in the study by means of a telephone questionnaire. Although daytime somnolence and the presence of apnoeas and snoring were the most frequently quoted clinical symptoms suggesting the diagnosis of SAHS, a combination of these symptoms was quoted in only one third of cases. On the other hand the complications of SAHS were not well known by GP's as only 25% of them mentioned the possibility of cardiovascular complications; cerebrovascular accidents and arterial hypertension being quoted by only 15% and 8.8% respectively. With regard to the follow up of patients treated with CPAP more than 50% of GP's did not know the minimum duration of ventilation required and 60% did not understand the method of function. These results, which emphasise the underestimation of SAHS and its complications, confirm the need to develop an educational strategy specifically for GP's in an attempt to improve the diagnosis of this disorder and to allow them to take part in the management and monitoring of treatment with CPAP.

Pharmacokinetic-pharmacodynamic modeling of electroencephalogram effect of imipenem in rats with acute renal failure.

The epileptogenic activity of imipenem was investigated in rats with experimental renal failure induced by uranyl nitrate injection by using electroencephalogram (EEG) recording and a pharmacokinetic-pharmacodynamic model including an effect compartment. Results previously obtained with healthy rats were used to estimate the dose of imipenem required to induce an observable but nonlethal EEG effect on the assumption that only the pharmacokinetic parameters of the model would be affected by renal failure. Good agreement was observed between the predicted and observed effects.